94 LS400 running rich. Need some advice!
#1
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94 LS400 running rich. Need some advice!
I've got a 94 LS400 that is literally driving me crazy! I bought the car as a project and I have to say, it has been kicking my butt! The starter was out when I bought it, so that was my first task that I had to take on. Got it finally up and going, but it was running like crap. Figured out that the ignition coils were the problem now. Replaced both coils and it was the difference between night and day. Now it has power, but it idles at approximately 1200 RPMs and hesitates when driving it. I've tried adjusting the throttle position sensor, but no difference. It's running extremely rich and exhausting black smoke. The check engine light is on and the trac light comes on and stays on after about 30 seconds running. For some reason, I'm unable to pull any CEL codes using a jumper wire. The check engine light will never start flashing any codes, just stays lit up solid. Bad TPS? Bad O2 sensor? Is there a way to test either of these? Any suggestions would be greatly appreciated!
#2
Lexus Champion
normally, when an LS400 will not communicate its OBD codes, and is not running right, it is nearly always a case of failing ECU capacitors
are you sure your jumper is in the correct location?
are you sure your jumper is in the correct location?
Last edited by LScowboyLS; 05-21-13 at 06:37 PM.
#3
normally, when an LS400 will not communicate its OBD codes, and is not running right, it is nearly always a case of failing ECU capacitors
are you sure your jumper is in the correct location?
are you sure your jumper is in the correct location?
#4
Had very similar issues
Sounds very similiar to issues I was recently having. I did coil packs, and hollowed out my catalytic converters because the honeycombs inside had broken up, and I also had to do both distributor caps and rotors inside them. When the distributor caps/rotors go bad, you get unburnt fuel in your plugs causing it to run rich and to have smoke and excess fuel etc. Check out my post that I did on the overview, if you scroll down youll seee where I did my dist caps and rotors.
https://www.clublexus.com/forums/ls4...-problems.html
https://www.clublexus.com/forums/ls4...-problems.html
#6
Driver School Candidate
I've got a 94 LS400 that is literally driving me crazy! I bought the car as a project and I have to say, it has been kicking my butt! The starter was out when I bought it, so that was my first task that I had to take on. Got it finally up and going, but it was running like crap. Figured out that the ignition coils were the problem now. Replaced both coils and it was the difference between night and day. Now it has power, but it idles at approximately 1200 RPMs and hesitates when driving it. I've tried adjusting the throttle position sensor, but no difference. It's running extremely rich and exhausting black smoke.
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